Update the gem description.

README.md

@@ -3,7 +3,7 @@
     <img src="https://i.imgur.com/qZrMsLq.png" alt="ogp" />
   </a>
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-  OGP is a minimalist Ruby library that does only one thing: parse Open Graph protocol information from web sites. For more information: <a href="http://ogp.me">http://ogp.me</a>.
+  OGP is a minimalist Ruby library that does only one thing: parse Open Graph protocol information. For more information: <a href="http://ogp.me">http://ogp.me</a>.
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   <a href="https://rubygems.org/gems/ogp"><img src="http://img.shields.io/gem/v/ogp.svg" /></a>
   <a href="https://codeclimate.com/github/jcouture/ogp"><img src="http://img.shields.io/codeclimate/github/jcouture/ogp.svg" /></a>